Two-step thermochemical cycles for CO2 splitting on Zr-doped cobalt ferrite supported on silica

Tong, Jinhui; Jiang, Qingqing; Chen, Zhenpan; Jiang, Zongxuan; Li, Can

doi:10.1016/j.solener.2015.04.007

Cited by 32 publications

(11 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Different kinds of CeO 2 derived oxygen carriers also yielded less than 250 µmol/g. Only some materials such as Co 0.8 Zr 0.1 Fe 2 O 4 /SiO 2 provided higher yields of around 800 µmol/g over 30 min but carried out by swinging between 1673 and 1373 K [15]. Hercynites are the only ones that provide comparable results to the current case, but they were looped via temperature swinging.…”

Section: Resultsmentioning

confidence: 64%

“…But these materials typically require reduction temperature as high 1800 K along with significant requirement of low partial pressures of O 2 for comparable oxygen storage capacity [10]. Iron oxide-based materials were also proposed of which substituted ferrite-based materials were found to provide higher performance in terms of lowered reduction temperature and higher oxygen storage capacity [11][12][13][14][15][16].…”

Section: Introductionmentioning

confidence: 99%

“…Similar to other iron oxide-based materials, these ferrites were found to be prone to high-temperature sintering which lowered their cycle performance from the loss of active surface area. To avoid this, ferrite deposition on high-temperature resilient substrates such as ZrO 2 , Al 2 O 3 , and yttrium stabilized zirconia (YSZ) were proposed and these studies showed formation of solid solution of Fe 2+ with the substrate during thermal reduction and thus providing structural stability [8,12,15,[18][19][20]. In the case of Al 2 O 3 , thermal reduction of M x Fe 3-x O 4 with Al 2 O 3 led to the formation of aluminates and reduction of Fe 3+ to Fe 2+ and thus releasing O 2 .…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Isothermal Splitting of CO2 to CO Using Cobalt-Ferrite Redox Looping

Burra

Gupta

Kerdsuwan

2020

Journal of Energy Resources Technology

View full text Add to dashboard Cite

Rising atmospheric CO2 levels from significant imbalance between carbon emissions from fossil fuel utilization, especially for energy and chemicals, and natural carbon sequestration rates is known to drive-up the global temperatures and associated catastrophic climate changes, such as rising mean sea level, glacial melting, and extinction of ecosystems. Carbon capture and utilization techniques are necessary for transition from fossil fuel infrastructure to renewable energy resources to help delay the dangers of reaching to the point of positive feedback between carbon emissions and climate change which can drive terrestrial conditions to uninhabitable levels. CO2 captured from the atmosphere directly or from flue gases of a power plant can be recycled and transformed to CO and syngas for use as energy and value-added chemicals. Utilizing renewable energy resources to drive CO2 conversion to CO via thermochemical redox looping can provide a carbon negative renewable energy conversion pathway for sustainable energy production as well as value-added products. Substituted ferrites such as Co-ferrite, Mn-ferrite were found to be promising materials to aid the conversion of CO2 to CO at lower reduction temperatures. Furthermore, the conversion of these materials in the presence of Al2O3 provided hercynite cycling, which further lowered the reduction temperature. In this paper, Co-ferrite and Co-ferrite-alumina prepared via co-precipitation were investigated to understand their potential as oxygen carriers for CO2 conversion under isothermal redox looping. Isothermal reduction looping provided improved feasibility in redox conversion since it avoids the need for temperature swinging which improves thermal efficiency. These efforts alleviate the energy losses in heat recovery while also reducing thermal stresses on both the materials and the reactor. Lab-scale testing was carried out at 1673 K on these materials for extended periods and multiple cycles to gain insights into cyclic performance and the feasibility of sintering, which is a common issue in iron-oxide-based oxygen carriers. Cobalt doping provided with lowering of reduction temperature requirement at the cost of oxidation thermodynamic spontaneity that required increased oxidation temperature. At the concentrations examined, these opposing phenomena made isothermal redox operation feasible by providing high CO yields comparable to oxygen carriers in the literature, which were operated at different temperatures for reduction and oxidation. Significantly high CO yields (~ 750 µmol/g) were obtained from Co-ferrite isothermal redox looping. Co-ferrite-alumina provided lower CO yields compared to Co-ferrite. The oxygen storage was similar to those reported in the literature on isothermal H2O splitting, but with improved morphological stability at high temperature, especially compared to ferrite. This pathway of oxygen carrier development is considered suitable with further requirement in optimization for scaling of renewable CO2 conversion into valuable products.

show abstract

Section: Resultsmentioning

confidence: 64%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Isothermal Splitting of CO2 to CO Using Cobalt-Ferrite Redox Looping

Burra

Gupta

Kerdsuwan

2020

Journal of Energy Resources Technology

View full text Add to dashboard Cite

show abstract

“…Thermochemical redox cycles driven by concentrated solar power (CSP) have been widely studied for simultaneous splitting of H 2 O and CO 2 for syngas (a mixture of H 2 and CO) production [43,44,50], which can be further processed to valuable compounds via established industrial processes like the Fischer-Tropsch process. Of the numerous multi-step thermochemical redox cycles that have been proposed, the two-step metal-oxide redox pair systems have shown considerable potential for synthetic solar fuel generation [40,49,55]. These thermochemical cycles utilize the transition between a higher valence oxidized (MeO oxd ) and lower valence reduced (MeO red ) form of a metal-oxide usually having multiple oxidation states [2].…”

Section: Introductionmentioning

confidence: 99%

Thermodynamic assessment of non-catalytic Ceria for syngas production by methane reduction and CO2 + H2O oxidation

Bose

Farooqui

Ferrero

et al. 2019

Mater Renew Sustain Energy

View full text Add to dashboard Cite

Chemical looping syngas production is a two-step redox cycle with oxygen carriers (metal oxides) circulating between two interconnected reactors. In this paper, the performance of pure CeO 2 /Ce 2 O 3 redox pair was investigated for low-temperature syngas production via methane reduction together with identification of optimal ideal operating conditions. Comprehensive thermodynamic analysis for methane reduction and water and CO 2 splitting was performed through process simulation by Gibbs free energy minimization in ASPEN Plus ®. The reduction reactor was studied by varying the CH 4 /CeO 2 molar ratio between 0.4 and 4 along with the temperature from 500 to 1000 °C. In the oxidation reactor, steam and carbon dioxide mixture oxidized the reduced metal back to CeO 2 , while producing simultaneous streams of CO and H 2 respectively. Within the oxidation reactor, the flow and composition of the mixture gas were varied, together with reactor temperature between 500 and 1000 °C. The results indicate that the maximum CH 4 conversion in the reduction reactor is achieved between 900 and 950 °C with CH 4 /CeO 2 ratio of 0.7-0.8, while, for the oxidation reactor, the optimal condition can vary between 600 and 900 °C based on the requirement of the final product output (H 2 /CO). The system efficiency was around 62% for isothermal operations at 900 °C and complete redox reaction of the metal oxide.

show abstract

“…Many factors including the crystal nature and size of the photocatalyst affect the band gap value. Numerous researchers have reported the potential applications of TiO 2 nanoparticles as a photocatalyst for the degradation of various organic compounds [6,7].…”

Section: Introductionmentioning

confidence: 99%

Photocatalytic Degradation of Organics by Using Nanocrystalline Titania

Ahmad¹,

Nazir²,

Hussain³

2017

Journal of Chemistry

View full text Add to dashboard Cite

Titanium dioxide nanoparticles were prepared by a modified sol-gel route. Titanium butoxide was used as precursor and nebulizer was used for a fine spray of particles. The prepared powders were characterized by FT-IR, SEM, XRD, and TGA-DTA methods. The results indicated that nanoparticles with small size and high surface area were synthesized. XRD result indicated that TiO2 nanoparticles were obtained in pure anatase crystalline form with a crystallite size of 40 nm. The catalytic activity of as-synthesized nanoparticles was tested for the degradation of formic acid and toluene.

show abstract

Two-step thermochemical cycles for CO2 splitting on Zr-doped cobalt ferrite supported on silica

Cited by 32 publications

References 41 publications

Isothermal Splitting of CO2 to CO Using Cobalt-Ferrite Redox Looping

Isothermal Splitting of CO2 to CO Using Cobalt-Ferrite Redox Looping

Thermodynamic assessment of non-catalytic Ceria for syngas production by methane reduction and CO2 + H2O oxidation

Photocatalytic Degradation of Organics by Using Nanocrystalline Titania

Contact Info

Product

Resources

About